1. Field of the Invention
This invention relates to a multi function steering mechanism for a motor vehicle and conversion kits for providing such multi function mechanism.
2. Background of the Invention
For a considerable period it has been the practice to mount control devices for various functions on a conventional steering column. There is, however, a practical limit to the number of manually actuable switches which may be conveniently disposed on the steering column.
Attempts have been made to dispose such switches on the steering wheel itself. The vehicle horn has, for example, been disposed centrally in the steering wheel when it is not disposed on a column projecting therefrom. When only one such device is used, or even more than one device, conventional slip rings and wiper devices such as that disclosed in U.S. Pat. No. 4,157,854 issued June 12, 1979 to Beauch may be used to convey electricity between the non-rotatable support column and the rotatable steering shaft on wheel for each device. When more than a very few switches are to be used, each controlling a different function, the slip ring arrangement becomes impracticable due to the limit on the number of slip rings which may be disposed between the steering wheel and the support column.
Since non-rotatable display panels within the periphery of the steering wheel are very desirable both from a design point of view and for practicality, numerous attempts have been made to solve the problems presented. The solutions provided have generally been electrically complex and sophisticated.
For example, U.S. Pat. No. 4,616,224 issued Oct. 7th, 1986 to Reighard discloses a transmitter/receiver pair to convey information relative to the operation of devices between the steering wheel and the support column; U.S. Pat. No. 4,456,903 issued June 26th, 1984 to Kishi et al discloses an optical signal transmission system; U.S. Pat. No. 4,438,425 issued Mar. 20th, 1984 to Tsuchida et al and U.S. Pat. No. 4,321,474 issued Mar. 23, 1982 to Tanaka et al discloses multiplexing signals from switches on the steering wheel and a light emitting device to generate a signal in response to the multiplexed output signal, a decoder unit being provided to decode the output signal of the light emitting device; and U.S. Pat. No. 4,635,029 issued Jan. 6th, 1987 to Yamada again utilizes light to transmit information between a stationary unit and a control board mounted on a steering wheel, light emitting and receiving means being provided on each of the statutory unit and the control board. Such electrical systems may be complex, expensive and sophisticated.
Willet, in U.S. Pat. No. 3,548,128 patented Dec. 15, 1970 discloses a steering wheel having a stationary central display which may be wired directly without the need for sophisticated pick ups from the electrical signals. Willets arrangement includes a central stationary stub carrying the wiring and an outer coaxial tube carrying the steering wheel and rotatable around the central stub.
Edmundts et al, in U.S. Pat. No. 4,429,588 patented Feb. 7, 1984 also discloses a steering wheel having a stationary central display which may be wired directly Edmundts' arrangement necessitates the axis of the steering wheel being offset from the axis of the steering column..
Various mechanical devices may be utilized to maintain a display panel central of the steering wheel non-rotatable with respect thereto. U.S. Pat. No. 4,368,454, for example, discloses one such system.
An attempt has now been made to devise a simple mechanical system utilizing direct connection of wiring to a non-rotatable display Panel within the periphery of the steering wheel, with a view to providing an inexpensive robust alternative to the various remotely operated systems referred to, and also with a view to providing improvements over the mechanical devices of Willet and Edmunts et al.